1. Field of the Invention
The present invention relates to a substrate holding apparatus which rotates together with a substrate while supporting an outer circumferential side surface of the substrate, and an inspection or processing apparatus of a substrate using this substrate holding apparatus.
2. Description of Related Art
In a manufacturing process of a product such as a semiconductor device, a thin display and a magnetic disk, a substrate such as a semiconductor wafer, a glass substrate and a disk substrate is processed, and the processed substrate is inspected. In many cases, the processing and the inspection of the substrate are performed while rotating the substrate. For example, in surface inspection for determining whether a defect such as a flaw or a foreign material is present on a surface of the semiconductor wafer or not, the inspection light scans the surface of the semiconductor wafer in a spiral manner by moving an irradiation region of the inspection light in a radial direction while rotating the semiconductor wafer, to detect the defect or the foreign material on the entire surface of the semiconductor wafer in a short time.
Moreover, in the case of the product such as a semiconductor device, a thin display and a magnetic disk, there is a tendency to control and reduce a defect and a foreign material generated also on a backside of the substrate with miniaturization of a circuit pattern, etc. For this reason, in the manufacturing process thereof, it is necessary to process and inspect the substrate in a non-contact state, not only on the front surface but also on the backside of the substrate.
Accordingly, a substrate holding apparatus which rotates the substrate in a non-contacting state with respect to the front surface and the backside thereof has been proposed (for example, see Paragraphs 0024-0039 and FIGS. 1-4 of JP-A-2004-253756).